Feltner will be called up from Double-A Hartford on Sunday, Nick Groke of The Athletic reports.
A fourth-round pick by the Rockies in 2018, Feltner posted stellar numbers in the minors this year to earn his first call-up. After going 3-1 with a 2.17 ERA with High-A Spokane to begin the season, Feltner got the bump up and hardly missed a beat with a 2.85 ERA in 72.2 innings with Hartford. Feltner is a candidate to step into the rotation immediately with Austin Gomber (back) done for the season. Ashton Goudeau is another option for Colorado.